From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1S7bcX-00008n-FJ for user-mode-linux-devel@lists.sourceforge.net; Tue, 13 Mar 2012 23:59:13 +0000 Received: from a.ns.miles-group.at ([95.130.255.143] helo=radon.swed.at) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1S7bcW-0005Ud-1B for user-mode-linux-devel@lists.sourceforge.net; Tue, 13 Mar 2012 23:59:13 +0000 Message-ID: <4F5FDF42.90004@nod.at> Date: Wed, 14 Mar 2012 00:58:58 +0100 From: Richard Weinberger MIME-Version: 1.0 References: <4F5FCC7D.5090307@panasas.com> In-Reply-To: <4F5FCC7D.5090307@panasas.com> List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net Subject: Re: [uml-devel] UML: Please help with __module_text_address crashing To: Boaz Harrosh Cc: uml-devel Am 13.03.2012 23:38, schrieb Boaz Harrosh: > Since a while now my UMLs are constantly crashing in __module_text_address > > which makes no sense because if I do gdb> list *(__module_text_address+0xd) > I get: > > 0x6005614e is in __module_text_address (/media/usr0/export/dev/bharrosh/git/pub/linux-open-osd/kernel/module.c:3469). > 3464 * module doesn't get freed during this. > 3465 */ > 3466 struct module *__module_text_address(unsigned long addr) > 3467 { > 3468 struct module *mod = __module_address(addr); > 3469 if (mod) { > 3470 /* Make sure it's within the text section. */ > 3471 if (!within(addr, mod->module_init, mod->init_text_size) > 3472&& !within(addr, mod->module_core, mod->core_text_size)) > 3473 mod = NULL; > > It can not be crashing in line 3469, I suspect it's crashing inside __module_address(addr); at line 3468 > > Below it's crashing as part of the console operation, which is the most common one, but it can crash in > __module_text_address as part of other stack traces like networking and so on. From my feel it's always > related to some UML driver that actually operates as part of the host. But I can't be sure. > > I'm running with 3.3-rc4 but I'm hit with this since 3.0, I tried to bisect > this at the time, but I found out that I could not find a perfectly good point > even as far as 3.6.37. So I suspected there is something wrong with my uml-image file > or my host. But now I upgraded both host and image to FC15 (was FC12/FC13) and I get > the same exact crashes. It came to a situation that I can't complete any kind > of heavy operation anymore and have abandoned UML for VMS for now. But I'm > very sorry to see UML go. > > Can anyone help me with some insight on what I should try, to debug this thing. > What exactly triggers the crash? IOW, how can I reproduce it? > BTW: > How to debug UML under gdb, it forks like mad and if I do: > gdb> set detach-on-fork off > It will just freeze. And if I do > gdb> attach > (Try to attach to any but the top parent process) > Will return "access not permitted". I guess UML is a debugger of sorts and it can't be > double debugged. e.g: $ gdb linux (gdb) handle SIGSEGV noprint nostop pass (gdb) set args (gdb) run UML "forks like mad" because it creates an thread for each process within UML... Thanks, //richard ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel